mirror of https://github.com/rusefi/wideband.git
32 lines
757 B
C++
32 lines
757 B
C++
#include "lambda_conversion.h"
|
|
#include "sampling.h"
|
|
|
|
static float GetPhi(float pumpCurrent)
|
|
{
|
|
// Maximum lambda ~2
|
|
if (pumpCurrent > 1.11f)
|
|
{
|
|
return 0.5f;
|
|
}
|
|
|
|
// Minimum lambda ~0.5
|
|
if (pumpCurrent < -3.5f)
|
|
{
|
|
return 1 / 0.5f;
|
|
}
|
|
|
|
// This estimation is accurate within 0.5% from 0.8 to 1.0, and 0.01% from 1 to 1.2 lambda when compared to the lookup table in the Bosch datasheet
|
|
// This error is less than half of the claimed accuracy of the sensor itself
|
|
float gain = pumpCurrent < 0 ? -0.28299f : -0.44817f;
|
|
|
|
return gain * pumpCurrent + 0.99559f;
|
|
}
|
|
|
|
float GetLambda()
|
|
{
|
|
float pumpCurrent = GetPumpNominalCurrent();
|
|
|
|
// Lambda is reciprocal of phi
|
|
return 1 / GetPhi(pumpCurrent);
|
|
}
|